TWI704023B - Control device of laser processing machine, laser processing method and laser processing machine - Google Patents

Abstract

The invention provides a laser processing machine control device capable of reducing the deviation between the incident position of a laser beam after a beam scanner is calibrated and the target incident position. The control device controls a laser processing machine with a beam scanner that scans the pulsed laser beam output from the laser light source, thereby moving the incident position of the pulsed laser beam on the surface of the processing object. The control device has the function of controlling the output timing of the pulsed laser beam from the laser source, indicating the target position of the pulsed laser beam to the beam scanner, and performing the beam scanner according to the pulse frequency during actual processing. The function of calibration.

Description

Control device of laser processing machine, laser processing method and laser processing machine

This application claims priority based on Japanese Patent Application No. 2017-204857 filed on October 24, 2017. All the contents of this application are used in this specification by reference.　　 The present invention relates to a control device of a laser processing machine, a laser processing method, and a laser processing machine.

There is known a laser processing machine that makes a pulsed laser beam incident on an object to be processed through a beam scanner and a condenser lens and processes it (for example, Patent Document 1). In order to make the pulsed laser beam incident on the target position as the processing object, the beam scanner is calibrated before the actual processing. (Prior Art Document) (Patent Document) 　　Patent Document 1: JP 2004-66300 A

(Problem to be solved by the present invention) 　　 It is clarified that despite the calibration of the beam scanner, the actual incident position of the pulsed laser beam sometimes deviates from the target position. The object of the present invention is to provide a laser processing machine control device, a laser processing method, and a laser processing machine that can reduce the deviation between the incident position of the laser beam after the beam scanner is calibrated and the target incident position. (Means for Solving the Problem) 　　According to an aspect of the present invention, 　　 provides a control device for a laser processing machine. The control device controls the laser processing machine with a beam scanner, and the beam scanner scans the output from the laser light source. The pulsed laser beam moves the incident position of the pulsed laser beam on the surface of the object to be processed. The aforementioned control device has: 　　 controls the output timing of the pulsed laser beam from the aforementioned laser light source; 　　 will make the pulse laser The target position of the beam incident is indicated to the function of the beam scanner; and the function of calibrating the beam scanner according to the pulse frequency during actual processing. According to another aspect of the present invention, 　　 provides a laser processing method, which uses a beam scanner to scan a pulsed laser beam output from a laser light source and make it incident on a plurality of processed points on the surface of the processed object in sequence. Processing, 　　The aforementioned laser processing method is based on the actual processing pulse frequency, while outputting a pulsed laser beam, the pulsed laser beam is incident on a plurality of parts of the evaluation sample, 　　according to the actual incident position of the pulsed laser beam Perform the aforementioned beam scanner calibration. According to another aspect of the present invention, a laser processing machine is provided, which has: a laser light source, which outputs a pulsed laser beam; and a beam scanner, which scans the pulsed laser beam output from the aforementioned laser light source, thereby enabling the processing object The incident position of the pulsed laser beam on the object surface moves; and a control device having the function of controlling the output timing of the pulsed laser beam from the aforementioned laser light source, and instructs the target position of the pulsed laser beam to be incident to the aforementioned beam scanning The function of the beam scanner and the function of calibrating the beam scanner according to the pulse frequency during actual processing. (Effects of the invention) 　　 can reduce the deviation between the incident position of the laser beam after the beam scanner is calibrated and the target incident position.

Referring to FIG. 1, the laser processing machine of the embodiment will be described.　　 Figure 1 is a schematic diagram of the laser processing machine of the embodiment. The laser light source 10 outputs a pulsed laser beam. As the laser light source 10, for example, a carbon dioxide laser oscillator can be used. The pulsed laser beam output from the laser light source 10 passes through the acousto-optic element (AOM) 11, the mirror 12, the beam scanner 13, and the condenser lens 14 to enter the processing object 30 held on the stage 17.　　 AOM 11 cuts out a part of the laser pulse of the pulsed laser beam output by the laser light source 10 for processing according to the instruction from the control device 20. The cut laser pulse enters the object 30 to be processed, and the remaining pulse laser beam enters the beam damper 15. The "beam scanner 13" receives instructions from the control device 20 and scans the laser beam in a two-dimensional direction, thereby moving the incident position of the pulsed laser beam on the surface of the object 30 to be processed. As the beam scanner 13, for example, a current scanner having a pair of current mirrors can be used. The "condenser lens 14" condenses the pulsed laser beam scanned by the beam scanner 13 on the surface (surface to be processed) of the object 30 to be processed. As the condenser lens 14, for example, an fθ lens can be used.　　The stage 17 receives an instruction from the control device 20, and moves the object 30 to be processed in a two-dimensional direction parallel to the surface. As the stage 17, for example, an XY stage can be used. An imaging device 16 is arranged above the 　　 stage 17. The imaging device 16 images the surface of the object to be processed 30 or the evaluation sample held on the stage 17, and generates image data. The image data generated by the imaging device 16 is read into the control device 20.　　 The control device 20 has a function of controlling the output timing of the pulsed laser beam from the laser light source 10. Furthermore, the control device 20 has a function of instructing the beam scanner 13 to the target position where the pulsed laser beam is incident. Furthermore, the control device 20 has a function of detecting the incident position of the pulsed laser beam by analyzing the image data acquired by the imaging device 16 and calibrating the beam scanner 13 based on the detection result.　　 The memory device 21 stores information required for laser processing, such as position information of the processed point of the processing object 30, processing sequence information, and calibration result information of the beam scanner 13, etc.　　 In addition, on the optical path of the pulsed laser beam from the laser light source 10 to the object to be processed 30, a lens system, an aperture, etc. may be arranged as necessary.　　 Next, referring to FIG. 2, the optical path from the laser light source 10 to the object 30 of the laser processing machine of the embodiment will be described. In FIG. 2, a virtual lens 35 is used to represent the optical system arranged on the optical path from the laser light source 10 to the object 30 to be processed. The virtual lens 35 images the exit 10A of the laser light source 10 on the imaging point Pi. In addition, the image point of the exit 10A may be formed on the optical axis of the optical system from the laser light source 10 to the object to be processed 30, but even in this case, the exit 10A is finally formed on the image point Pi. In addition, there are also time circles arranged at the position of the image point. "In a state where the surface of the object to be processed 30 is arranged at a position shifted from the imaging point Pi to the optical axis direction (height direction in FIG. 1) of the optical system, the stage 17 (FIG. 1) holds the object to be processed 30. For example, the stage 17 has a lifting function, and the control device 20 controls the stage 17 to realize the state of deviation. If the surface of the object 30 to be processed is arranged at a position away from the imaging point Pi, it is possible to reduce the beam spot on the surface of the object 30 to be smaller. "According to the verification test of the inventor of the present application, it is clarified that if the pulse frequency of the pulsed laser beam output from the laser light source 10 is changed, the emission direction of the laser beam may change. Even if the emission direction of the laser beam changes, the position of the imaging point Pi does not change. In the case of processing on the imaging point Pi, there will be no deviation in the processing position. "However, if the surface of the object 30 to be processed is arranged at a position away from the imaging point Pi, the incident position of the pulsed laser beam changes in accordance with the change in the emission direction. For example, the pulse laser beam along the optical path OP1 is incident on the point P1 on the surface of the object 30, and the pulse laser beam along the optical path OP2 is incident on the point P2 on the surface of the object 30. For example, if the beam scanner 13 is calibrated with the pulse frequency of the laser beam along the optical path OP1, and the laser beam along the optical path OP2 is used for processing, the incident position of the pulsed laser beam during processing will deviate from the target position. .　　 Next, referring to Figs. 3 and 4, the laser processing method using the laser processing machine of the embodiment will be described.　　 FIG. 3 is a schematic plan view of the object 30 to be processed. A plurality of unit scanning areas 31 are divided on the surface of the object 30 to be processed. A plurality of to-be-processed points 32 are divided in the unit scanning area 31. The beam scanner 13 (FIG. 1) can be operated without moving the object 30 to be processed, and thereby the pulsed laser beam can be incident on any part within one unit scanning area 31. "When the processing in one unit scanning area 31 is completed, the stage 17 is driven to move the unprocessed unit scanning area 31 to a position that can be scanned by the beam scanner 13. By repeating this process, all the unit scanning areas 31 can be processed.　　 Figure 4 is a flowchart of the laser processing method using the laser processing machine of the embodiment. First, the control device 20 acquires information related to the pulse frequency during actual processing (step S1). Hereinafter, the method of acquiring information related to the pulse frequency during actual processing will be explained.　　 The memory device 21 stores the position information and the processing sequence information of a plurality of processed points divided on the surface of the processing object 30. During processing, after the pulsed laser beam is incident on a processed point, the control device 20 indicates the target position to the beam scanner 13, and then moves the incident position of the laser beam to the position of the processed point to be processed . After the beam scanner 13 is stabilized, the control device 20 instructs the laser light source 10 to output a pulsed laser beam. When the distance from one point to be processed to the next point to be processed is long, the time until the beam scanner 13 becomes stable becomes long. Therefore, the pulse interval of the pulsed laser beam becomes longer (the pulse frequency is reduced). "The control device 20 does not output the pulsed laser beam from the laser light source 10, but makes the beam scanner 13 operate so that the incident position of the pulsed laser beam sequentially follows a plurality of processing points of the object 30 to be processed. At this time, for all the processed points, the time until the beam scanner 13 is stabilized is measured. After the incident position of the laser beam follows all the processed points in the unit scanning area 31 (Figure 3) in turn, information related to the pulse frequency is obtained. This process is executed for all unit scanning areas 31. For example, the information related to the pulse frequency includes the stabilization time of the beam scanner 13 for each processed point in each unit scanning area 31, and the time for the pulse laser beam to enter the processed point after stabilization (from the pulse laser beam The delay time, pulse width, etc. from the output instruction to the actual output of the pulsed laser beam). "After step S1, the sample for evaluation is held on the stage 17, and the height of the surface of the sample for evaluation and the surface of the object 30 at the time of processing are made to match. The control device 20 determines the pulse frequency based on information related to the pulse frequency during actual processing. The pulsed laser beam is output from the laser light source 10 at the determined pulse frequency, so that the pulsed laser beam is incident on a plurality of positions for calibration (step S2). When the beam scanner 13 fails to stabilize in time until the laser pulse is output, the laser pulse is incident on the beam damper 15 until the beam scanner 13 is stabilized (FIG. 1). "The pulse frequency of the pulsed laser beam incident on the evaluation sample may be, for example, the frequency between the maximum value and the minimum value of the pulse frequency when all the unit scanning areas 31 are actually processed, acquired in step S1. For example, it is sufficient to set statistics such as the average value, mode value, and median value of the pulse frequency during actual processing. "After step S2, the control device 20 drives the stage 17 to arrange the evaluation sample within the angle of view of the imaging device 16, and photographs the evaluation sample, and acquires image data. The incident position of the pulsed laser beam is detected by analyzing the image data, and the incident position information is acquired (step S3). "After step S3, the control device 20 performs calibration of the beam scanner 13 based on the incident position information of the pulsed laser beam acquired in step S3 and the indication value of the target position of the beam scanner 13 (step S4). The calibration result is stored in the memory device 21. "After step S4, the object to be processed 30 is held on the stage 17 and actual processing is performed (step S5). Until the processing of all the processing objects 30 is completed, step S5 is repeated (step S6).　　 Next, the excellent effects of the laser processing machine of the embodiment will be described. "In this embodiment, the pulse frequency during calibration is determined according to the pulse frequency during actual machining, so the accuracy of calibration can be improved. This can reduce the positional deviation of the incident position of the laser beam during processing.　　 Next, a modification of the above-mentioned embodiment will be described. "In the above-mentioned embodiment, in step S1 (FIG. 4), the information related to the pulse frequency during processing is acquired based on the action of the beam scanner 13 during actual processing. As another method, you can fix the pulse frequency during processing in advance and perform processing with a constant pulse frequency. When the beam scanner 13 fails to stabilize in time until the laser pulse is output, the laser pulse output during the period until the beam scanner 13 stabilizes is incident on the beam damper 15 (FIG. 1 ). The pulse frequency of the pulsed laser beam incident on the evaluation sample in step S2 may be the same as the pulse frequency that is fixed during actual processing. "In addition, in the above-mentioned embodiment, the statistic of the pulse frequency when processing all the unit scanning areas 31 (FIG. 3) in the processing object 30 is set as the pulse frequency at the time of calibration. In the case where the distribution density of the processed points in the plurality of unit scanning areas 31 has a large difference, the statistics of the pulse frequency during actual processing have a large difference in each unit scanning area 31. In this case, it is sufficient to calibrate the beam scanner 13 for each unit scanning area 31. The calibration result is stored in the memory device 21 for each unit scanning area 31. In the case of processing the unit scanning area 31, the result of calibration of the unit scanning area 31 may be used to drive the beam scanner 13. In the above-mentioned embodiment, the surface of the object 30 is arranged at a position deviated from the imaging point Pi (FIG. 2) and processed, but the surface of the object 30 is processed without deviating the surface of the object 30 from the imaging point Pi (FIG. 2). The effect can also be obtained under the circumstances. For example, even when the position of the imaging point Pi does not deviate, if the optical path to the imaging point Pi changes, the attenuation rate of the light intensity may also change. If the beam scanner 13 is calibrated by the method of this embodiment, the optical path of the pulsed laser beam is substantially fixed, so the fluctuation of the light intensity can be suppressed, and the stability of the position detection result during calibration can be improved.　　 The above-mentioned embodiments and modifications are examples, and it is of course possible to make partial replacements or combinations of the configurations shown in the embodiments and modifications. Regarding the same action and effect based on the same configuration of the embodiment and the modification, each embodiment and the modification will not be described one by one. Furthermore, the present invention is not limited to the above-mentioned embodiments and modifications. For example, it is obvious to those skilled in the art that various changes, improvements, and combinations can be made.

10‧‧‧Laser light source 10A‧‧‧Laser exit 11‧‧‧Acousto-optic element (AOM) 12‧‧‧Reflector 13‧‧‧Beam scanner 14‧‧‧Condenser lens 15‧‧‧Beam Damper 16‧‧‧Camera device 17‧‧‧Platform 20‧‧‧Control device 21‧‧‧Memory device 30‧‧‧Processing object 31‧‧‧Unit scanning area 32‧‧‧Processing point 35‧ ‧‧Virtual lens

Fig. 1 is a schematic diagram of the laser processing machine of the embodiment.　　 Figure 2 is a schematic diagram showing the optical path from the laser light source to the object to be processed.　　 Figure 3 is a schematic plan view of the object to be processed.　　 Figure 4 is a flowchart of the laser processing method using the laser processing machine of the embodiment.

Claims (7)

A control device for a laser processing machine, the control device controls the laser processing machine with a beam scanner, and the beam scanner scans the pulsed laser beam output from the laser light source, thereby causing the pulse in the surface of the processing object The incident position of the laser beam moves, and the control device has the function of controlling the output timing of the pulsed laser beam from the laser light source; and instructing the target position of the pulsed laser beam incident to the beam scanner ; And the function of calibrating the aforementioned beam scanner according to the pulse frequency during actual processing. The control device for a laser processing machine described in the first item of the scope of patent application, wherein the laser processing machine further has an imaging device for photographing the surface of the object to be processed, and controls the laser light source according to the pulse frequency during actual processing And the beam scanner, so that the pulsed laser beam is incident on a plurality of parts of the evaluation sample, and the image obtained by the imaging device captured by the imaging device on the surface of the evaluation sample after the pulsed laser beam is incident is analyzed Data to obtain the incident position information of the aforementioned pulsed laser beam, According to the obtained incident position information, the beam scanner is calibrated. According to the control device of the laser processing machine described in item 1 or 2 of the scope of patent application, the control device further has the following function: located on the surface of the processing object at the exit of the pulsed laser beam from the laser light source In the state where the imaging point deviates from the position, the laser light source and the beam scanner are controlled. According to the control device of the laser processing machine described in item 1 or 2 of the scope of patent application, the control device also has the function of not causing the pulsed laser beam to be output from the laser light source, but making the beam scanner The operation is performed in such a manner that the pulsed laser beam is sequentially incident on a plurality of processed points of the object to be processed, thereby obtaining information about the pulse frequency of the pulsed laser beam during actual processing. A laser processing method that scans a pulsed laser beam output from a laser light source with a beam scanner and makes it incident on a plurality of processed points on the surface of an object to be processed sequentially. The foregoing laser processing method is based on The pulse frequency during the actual processing, while outputting the pulsed laser beam, the pulsed laser beam is incident on a plurality of parts of the evaluation sample. According to the actual incident position of the pulsed laser beam, the beam scanner is calibrated. The laser processing method described in claim 5, wherein the surface of the object to be processed is located at a position deviated from the imaging point of the exit of the pulsed laser beam of the laser light source, further performing Processing. A laser processing machine, which has: a laser light source that outputs a pulsed laser beam; a beam scanner that scans the pulsed laser beam output from the laser light source, thereby causing the pulsed laser on the surface of the processing object The incident position of the light beam moves; and a control device that has the function of controlling the output timing of the pulsed laser beam from the laser light source, the function of indicating the target position of the pulsed laser beam incident to the beam scanner, and Perform the calibration function of the beam scanner according to the pulse frequency during actual processing.

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